Not Applicable
Not Applicable
This invention pertains to the removal of gimbal bearings used in marine propulsion systems known as stern drives.
A gimbal bearing is located in a housing known as a transom bracket, and is press fit into said bracket. The bearing is shrouded by another housing known as a bell housing which is attached to the transom bracket with pins, hoses and cables. The result is a bearing that is difficult to access through the bell housing, and time consuming to access by removing the bell housing. Existing methods rely largely on universal pullers with multiple fingers or jaws that expand behind the bearing and are attached to a slide hammer or a screw and plate arrangement. These methods require a time consuming and difficult set up of a tool within the restrictive and often greasy confines of the bell housing. The fingers frequently cannot support the load needed to remove the bearing and flex and come out of the bearing before it can be removed, requiring a repeat set up. Slide hammers sometimes do not have the force needed to jar the bearing loose. Plate and screws methods are generally more difficult to set up than the slide hammer.
The present invention consists of a fixed hook that is pushed through the center of the bearing to be removed. Once the hook has passed through the bearing, the hook automatically locates itself behind the bearing, propelled by forces generated by a spring loaded slide locking mechanism. Once the bearing is properly located, the locking mechanism itself automatically passes through the center of the bearing, effectively taking up all of the space within the inside diameter of the bearing. This makes it impossible for the hook to escape from behind the bearing until the lock is manually released.
A threaded rod is attached to the opposite end of the hook body. An offset arm is also located on the same end of the hook body.
A flange is used to bridge across the opening of the bell housing. This flange provides the platform necessary for the removing force to be transmitted to the bearing. The flange is specifically shaped to fit over the studs on the bell housing.
The threaded rod is passed through the center of the flange. The offset arm referred to as the torque arm passes through a hole offset to one side of the flange. The torque arm prohibits the hook body from rotating.
A thrust bearing is mounted on the nut side of the flange. An abnormally elongated nut is threaded onto the threaded rod. The nut is elongated for three purposes; first it provides the extra threaded surface area needed to support the required loads. Second, it provides a handle for controlling the tool. Third, it absorbs the threaded rod as the nut is tightened as to prevent the threaded rod from interfering with the tool used to tighten it.
As the nut is tightened, the distance between the hook body and the flange is reduced, this removes the bearing from its housing.
A handle on the slide locking mechanism is provided to manually release the lock from the center of the bearing, allowing the bearing to pass back over the hook and off the tool.
The present invention solves the problems of prior art by providing a completely automatic setup within the bell housing, as well as eliminating flexing problems by utilizing the inside diameter of the bearing to support the hook. The present invention utilizes the benefits of a screw and plate extraction system over a slide hammer without any of the set up problems associated with existing plate and screw type pullers.